1. Field of the Invention
The invention relates to a semiconductor device, and particularly relates to a structure for suppressing current leakage and a semiconductor device including the structure for suppressing current leakage.
2. Description of Related Art
Recently, as people are gaining the awareness of environmental protection, high voltage power integrated circuits featuring low power consumption and high power conversion efficiency are drawing more and more attention. Generally speaking, the high voltage power integrated circuits are mainly used in power switch devices and applied in the fields of switching mode power supply (SMPS), luminaire, motor control, or plasma display driver, etc.
In the high voltage power integrated circuits, high voltage semiconductor devices and low voltage logic control circuits are integrated in a single chip. The high voltage power integrated circuits accordingly have several advantages, such as high reliability, high stability, low power consumption, small size, and low cost, etc. While the high voltage semiconductor devices are capable of taking a high voltage at hundreds of volts, they are controlled by the low voltage logic control circuits operated at tens of volts or lower. To make the low voltage control circuits suitable for the high voltage semiconductor devices, level shifters are commonly used to shift a low voltage signal to a higher voltage level. Isolation between adjacent transistors in the level shifters has been an issue that researchers in relevant industries are working on. Thus, a structure capable of effectively suppressing current leakage is required to improve the isolation between the adjacent transistors.